Patient History
64-year-old female with right hip pain after removal of hip prosthesis
Findings
SKELETAL: Susceptibility effect and aspect ratio geometric distortion are consistent with hip prosthesis most likely containing components of cobalt and nickel. The interface between the stem and skeleton is preserved. No exuberant heterotopic bone. No evidence of fracture or stress fracture.
PELVIS: A pelvic mass projects both laterally as a complex fluid collection and medially as a pseudomass into the groin and is consistent with a complex particulate synovial reaction as a tumefactive 4.5 cm pseudolesion. Process most likely corresponds to dissection of such into the iliopsoas bursa.
JOINTS: Extensive synovial reaction and particulate reaction are consistent with aseptic lymphovascular associated lesion or ALVAL. Paucity of intraarticular susceptibility metallosis effect. Irregular dissecting capsulobursal pseudocyst surrounded by fibrous tissue is consistent with such.
ACETABULUM/LABRUM: Obscured by susceptibility effect and aspect ratio distortion but no evidence of insufficiency or stress fracture or pelvic periprosthetic hardware fracture noted.
MUSCLES/TENDONS/LIGAMENTS: Compression of surrounding soft tissues with atrophy of the abductor mechanism, severe. Gluteus medius and minimus and to a lesser extent maximus and piriformis are affected.
OTHER/SOFT TISSUE: Soft tissue masses described above.
Conclusion
Complex pattern of aseptic lymphovascular associated lesion or ALVAL with exuberant particulate reaction and at least 4.5 cm in diameter medially dissecting intermediate signal intensity pseudomass.
Little in the way of metallosis or metal reaction.
